.viewport {

}

.i_Btn-base

(
)
{
  background: none;
  display: inline-block;
  height: 28px;
  line-height: 28px;
  border-radius: $radius;
  text-align: center;
  vertical-align: middle;
  border: none;
  background: -webkit-linear-gradient(top, transparent, transparent);
  font-size: 14px;
}

.i_Btn {
  .i_Btn-base
;
  padding: 0 $space *2;
  border: 1px solid $btn-border;
  color: $btn-color;
  &:link, &:visited {
    color: $btn-color;
  }
  &:hover, &:active {
    border-color: $btn-active-border;
    background-color: $btn-active-bg;
    color: $btn-active-color;
  }
}
